Hinge device and electric power system

ABSTRACT

A hinge device includes: a first and a second hinge components having a common reference axis; and a power generating device. The first and the second hinge components are engaged with each other, so as to be rotatable about the reference axis relative to each other, and so that one of the first and the second hinge components supports the other. The power generating device includes a housing and an input shaft, and generates electric power by rotation of the input shaft. The housing of the power generating device is fixed to the first hinge component, so that the input shaft of the power generating device is positioned on the reference axis. The input shaft of the power generating device is restrained to the second hinge component with respect to the direction of rotation about the reference axis, so that the input shaft of the power generating device rotates by as much as rotation of the second hinge component when the second hinge component rotates about the reference axis.

TECHNICAL FIELD

The present invention relates to a hinge device provided with a powergenerating device, and relates to a power system including such a hingedevice.

BACKGROUND ART

In recent years, in consideration of fossil fuel depletion and globalwarming prevention, utilization of natural energy, and various kinds ofambient energy has been actively promoted. As utilization of the naturalenergy, for example, it is known to generate electric power using asolar cell or a wind power generator. In addition, as utilization of theambient energy, for example, it is known to generate electric powerusing energy obtained from a user's living activities (human-poweredgeneration), piezoelectric energy (vibration power generation), energyof electromagnetic waves such as broadcast waves, or the like. Toharvest and use the ambient energy is drawing attention as “energyharvesting”.

CITATION LIST Patent Documents

PATENT DOCUMENT 1: Japanese Patent Laid-open Publication No. JP2013-070520 A

SUMMARY OF INVENTION Technical Problem

As an exemplary human-powered generation using energy obtained from auser's living activities, Patent Document 1 discloses incorporating apower generating device into a sliding door and a revolving door. PatentDocument 1 refers to incorporating a power generating device into ahinge of a revolving door, but does not disclose how to implement thehinge with the power generating device being incorporated therein.Accordingly, it is required to incorporate a power generating deviceinto a hinge, so as to efficiently extract energy from a user's livingactivities to generate electric power.

The present disclosure provides a hinge device provided with a powergenerating device, the hinge device being capable of efficientlyextracting energy from a user's living activities to generate electricpower. The present disclosure also provides a power system includingsuch a hinge device.

Solution to Problem

According to an aspect of the present disclosure, a hinge device isprovided with: first and second hinge components having a commonreference axis; and a power generating device. The first and secondhinge components are engaged with each other, so as to be rotatableabout the reference axis relative to each other, and so that one of thefirst and second hinge components supports the other. The powergenerating device is provided with a housing and an input shaft, andgenerates electric power by rotation of the input shaft. The housing ofthe power generating device is fixed to the first hinge component, sothat the input shaft of the power generating device is positioned on thereference axis. The input shaft of the power generating device isrestrained to the second hinge component with respect to a direction ofrotation about the reference axis, so that the input shaft of the powergenerating device rotates by as much as rotation of the second hingecomponent when the second hinge component rotates about the referenceaxis.

Advantageous Effects of Invention

According to an aspect of the present disclosure, it is possible toprovide the hinge device provided with the power generating device, thehinge device being capable of efficiently extracting energy from auser's living activities to generate electric power.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram illustrating a configuration of a powersystem according to a first embodiment.

FIG. 2 is an exploded perspective view illustrating a configuration of apower generating device 3 including a gear mechanism G1 and a powergenerator M1 of FIG. 1.

FIG. 3 is a perspective view illustrating a first step of assembling ahinge device 10 of FIG. 1.

FIG. 4 is a perspective view illustrating a second step of assemblingthe hinge device 10 of FIG. 1.

FIG. 5 is a perspective view illustrating a third step of assembling thehinge device 10 of FIG. 1.

FIG. 6 is a perspective view illustrating a fourth step of assemblingthe hinge device 10 of FIG. 1.

FIG. 7 is a perspective view illustrating a first step of attaching thehinge device 10 of FIG. 1, to a door including a stationary object 21and a movable object 22.

FIG. 8 is a perspective view illustrating a second step of attaching thehinge device 10 of FIG. 1, to the door including the stationary object21 and the movable object 22.

FIG. 9 is a perspective view illustrating a third step of attaching thehinge device 10 of FIG. 1, to the door including the stationary object21 and the movable object 22.

FIG. 10 is a circuit diagram illustrating the configuration of the powersystem according to the first embodiment.

FIG. 11 is a schematic diagram illustrating operation of the powersystem according to the first embodiment.

FIG. 12 is a perspective view illustrating a first step of assembling ahinge device 10A of a power system according to a first modifiedembodiment of the first embodiment.

FIG. 13 is a perspective view illustrating a second step of assemblingthe hinge device 10A of the power system according to the first modifiedembodiment of the first embodiment.

FIG. 14 is a perspective view illustrating a third step of assemblingthe hinge device 10A of the power system according to the first modifiedembodiment of the first embodiment.

FIG. 15 is a perspective view illustrating a fourth step of assemblingthe hinge device 10A of the power system according to the first modifiedembodiment of the first embodiment.

FIG. 16 is a schematic diagram illustrating a configuration of a powersystem according to a second modified embodiment of the firstembodiment.

FIG. 17 is a schematic diagram illustrating a configuration of a powersystem according to a third modified embodiment of the first embodiment.

FIG. 18 is a schematic diagram illustrating a configuration of a powersystem according to a fourth modified embodiment of the firstembodiment.

FIG. 19 is a schematic diagram illustrating a configuration of a powersystem according to a fifth modified embodiment of the first embodiment.

FIG. 20 is a schematic diagram illustrating a configuration of a powersystem according to a sixth modified embodiment of the first embodiment.

FIG. 21 is a perspective view illustrating a first step of assembling ahinge device 10B of a power system according to a second embodiment.

FIG. 22 is a perspective view illustrating a second step of assemblingthe hinge device 10B of the power system according to the secondembodiment.

FIG. 23 is a perspective view illustrating a third step of assemblingthe hinge device 10B of the power system according to the secondembodiment.

FIG. 24 is a perspective view illustrating a first step of attaching thehinge device 10B of FIG. 18, to a door including a stationary object 21Band a movable object 22B.

FIG. 25 is a perspective view illustrating a second step of attachingthe hinge device 10B of FIG. 18, to the door including the stationaryobject 21B and the movable object 22B.

FIG. 26 is a perspective view illustrating a third step of attaching thehinge device 10B of FIG. 18, to the door including the stationary object21B and the movable object 22B.

FIG. 27 is a perspective view illustrating configurations of a powergenerating device 3 and a hinge component 2B according to a firstmodified embodiment of the second embodiment.

FIG. 28 is a perspective view illustrating configurations of a powergenerating device 3 and a hinge component 2B according to a secondmodified embodiment of the second embodiment.

FIG. 29 is a perspective view illustrating configurations of a powergenerating device 3 and a hinge component 2B according to a thirdmodified embodiment of the second embodiment.

FIG. 30 is a schematic diagram for illustrating operations of fourcapacitors C1 to C4 in a power system according to a third embodiment.

FIG. 31 is a schematic diagram for illustrating operation of onecapacitor in the power system according to the third embodiment.

FIG. 32 is a graph showing characteristics of available energy tocapacitance of a power system according to a first implementationexample of the third embodiment.

FIG. 33 is a graph showing characteristics of available energy tocapacitance of a power system according to a second implementationexample of the third embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings. In the drawings, similar components aredenoted by the same reference signs.

First Embodiment

FIG. 1 is a schematic diagram illustrating a configuration of a powersystem according to a first embodiment. The power system of FIG. 1 isincorporated into, for example, a door including a stationary object 21and a movable object 22.

The power system of FIG. 1 is provided with a hinge device 10, arectifier circuit 11, a power storage circuit 12, a controller circuit13, and a load device 14. The hinge device 10 is provided with a hingecomponent 1, a hinge component 2, and a power generating device 3. Thehinge component 1 is fixed to the stationary object 21 with a pluralityof screws 23. The hinge component 2 is fixed to the movable object 22with a plurality of screws 23. The power generating device 3 is providedwith a gear mechanism G1 and a power generator M1.

FIG. 2 is an exploded perspective view illustrating the configuration ofthe power generating device 3 including the gear mechanism G1 and thepower generator M1 of FIG. 1. The gear mechanism G1 is provided with ahousing 30 a, an input shaft 31, and a plurality of internal gears. Thepower generator M1 is provided with a housing 30 b, an internal rotorand an internal stator (not shown), and a gear 33 coupled to the rotor.Hereinafter, the housings 30 a and 30 b are collectively referred to asa “housing 30”. The gear mechanism G1 transmits rotation of the inputshaft 31 to the gear 33 of the power generator M1 at a certainincreasing gear ratio. The power generator M1 generates electric powerby rotation transmitted by the gear mechanism G1. Accordingly, the powergenerating device 3 generates electric power (voltage and current) byrotation of the input shaft 31. The gear mechanism G1 may include, forexample, a multi-stage planetary gear mechanism. Thus, it is possible tocompactly incorporate a gear mechanism having a large increasing gearratio, in alignment to the input shaft 31 of the power generator M1. Thegear mechanism G1 may have, for example, a cylindrical housing 30 a. Thecylindrical housing 30 is suitable for incorporating the gear mechanismG1 into a hinge device. As will be described with reference to FIGS. 3to 6, the input shaft 31 has a dent 32 on a side surface thereof, inorder to restrain the input shaft 31 to the hinge component 2. The powergenerator M1 may be a DC generator, or may be an AC generator.

The operation of the power generator and the operation of the motor arereversible. Accordingly, instead of using the gear mechanism G1 havingan increasing gear ratio, and the power generator M1, a motor and a gearmechanism having a certain decreasing gear ratio may be used. In thiscase, the gear mechanism transmits rotation of an output shaft to themotor, at an increasing gear ratio equal to a reciprocal of thedecreasing gear ratio. The motor then generates electric power byrotation transmitted by the gear mechanism.

FIGS. 3 to 6 are perspective views illustrating first to fourth steps ofassembling the hinge device 10 of FIG. 1.

As shown in FIG. 3, the hinge component 1 has a cylindrical portion anda planar portion coupled to each other. The cylindrical portion of thehinge component 1 has: a protrusion 1 a to be engaged with the hingecomponent 2, and a recess 1 b (hollow) accommodating the powergenerating device 3. The cylindrical portion of the hinge component 1 isfurther provided with a through hole 1 c at a position where the hingecomponent 1 and the hinge component 2 are engaged with each other, thethrough hole is being formed so that the input shaft 31 of the powergenerating device 3 protrudes from the hinge component 1 toward thehinge component 2. The planar portion of the hinge component 1 has aplurality of screw holes 1 d for fixing the hinge component 1 to thestationary object 21 with the plurality of screws 23. The hingecomponent 2 also has a cylindrical portion and a planar portion coupledto each other. The cylindrical portion of the hinge component 2 has arecess 2 a (hollow) into which the protrusion 1 a of the hinge component1 is engaged (inserted), and a screw hole 2 b penetrating the hingecomponent 2 from the outside of the hinge component 2 to the recess 2 a.The planar portion of the hinge component 2 has a plurality of screwholes 2 c for fixing the hinge component 2 to the movable object 22 withthe plurality of screws 23.

As shown in FIG. 4, the hinge component 1 and the hinge component 2 areengaged with each other, so as to be rotatable about a common referenceaxis (indicated by line A-A′ in FIG. 3) relative to each other, and sothat one of the hinge component 1 and the hinge component 2 supports theother. Since the protrusion 1 a of the hinge component 1 has an outercylindrical surface, and the recess 2 a of the hinge component 2 has aninner cylindrical surface, the hinge component 1 and the hinge component2 are engaged with each other so as to be rotatable relative to eachother. In addition, in the example of FIG. 4, the hinge component 2 isdisposed above the hinge component 1, and the hinge component 1 supportsthe hinge component 2. The cylindrical portion of the hinge component 1has two portions with different outer diameters. Thus, the weight of thehinge component 2 is applied to the hinge component 1, at a positionwhere the lower end of the cylindrical portion of the hinge component 2is in contact with the cylindrical portion of the hinge component 1. Inaddition, as shown in FIG. 4, the power generating device 3 is insertedinto the recess 1 b of the hinge component 1. The housing 30 of thepower generating device 3 is fixed to the hinge component 1 with anadhesive or a screw (not shown), so that the input shaft 31 of the powergenerating device 3 is positioned on the reference axis.

Except for the position where the hinge component 1 and the hingecomponent 2 are engaged with each other so as to be rotatable relativeto each other (i.e., the protrusion 1 a of the hinge component 1, andthe recess 2 a of the hinge component 2), the outer surfaces of thehinge component 1 and the hinge component 2 may not be cylindricallyshaped, but may be shaped as triangular prisms, quadrangular prisms,other polygonal prisms, other polyhedrons.

The recess 2 a of the hinge component 2 accommodates the input shaft 31of the power generating device 3 protruding through the through hole 1c. The input shaft 31 of the power generating device 3 is restrained tothe hinge component 2 with respect to the direction of rotation aboutthe reference axis, so that the input shaft 31 of the power generatingdevice 3 rotates by as much as rotation of the hinge component 2 whenthe hinge component 2 rotates about the reference axis. As describedwith reference to FIG. 2, the input shaft 31 of the power generatingdevice 3 has the dent 32 on the side surface of the input shaft 31.Accordingly, as shown in FIGS. 5 and 6, a screw 41 is inserted throughthe screw hole 2 b of the hinge component 2, such that the screw 41extends from the outside of the hinge component 2 to the recess 2 a soas to penetrate the hinge component 2 and contact with the dent 32 inthe recess 2 a. By the screw 41, the input shaft 31 of the powergenerating device 3 is restrained to the hinge component 2 with respectto the direction of rotation about the reference axis.

The hinge device 10 is made by engaging the hinge component 1 and thehinge component 2 with each other, fixing the housing 30 of the powergenerating device 3 to the hinge component 1, and restraining the inputshaft 31 of the power generating device 3 with respect to the hingecomponent 2 by the screw 41.

Since the hinge device 10 is configured as shown in FIGS. 3 to 6, thepower generating device 3 is incorporated in the hinge device 10. In thehinge device 10, the input shaft 31 of the power generating device 3protrudes from the through hole 1 c, and the input shaft 31 of the powergenerating device 3 is restrained to the hinge component 2 by the screw41. Accordingly, rotation of the hinge component 2 can be transmitted tothe power generating device 3 accommodated in the recess 1 b of thehinge component 1. Thus, it is possible to achieve such a configurationthat the power generating device 3 is incorporated in the hinge device10. Since the power generating device 3 is incorporated in the hingedevice 10, it is possible to provide the hinge device 10 having a goodappearance.

In addition, since the hinge component 1 supports the hinge component 2,the weight of the hinge component 2 and the movable object 22 is notapplied to the pourer generating device 3. The screw 41 does not have torestrain the input shaft 31 of the power generating device 3 to thehinge component 2 with respect to the longitudinal direction of thereference axis, but restrains the input shaft 31 to the hinge component2 with respect to at least the direction of rotational about thereference axis. Accordingly, it is possible to achieve such aconfiguration that the weight of the hinge component 2 and the movableobject 22 is not applied to the power generating device 3, while theinput shaft 31 of the power generating device 3 protrudes from thethrough hole 1 c and the input shaft 31 of the power generating device 3is restrained to the hinge component 2 by the screw 41. Since the weightof the hinge component 2 and the movable object 22 is not applied to thepower generating device 3, it is possible to reliably operate the powergenerating device 3, without applying an extra mechanical load to thepower generating device 3.

In addition, the hinge component 1 and the hinge component 2 having theconfiguration as shown in FIGS. 3 to 6 are engaged with each other so asto be detachable from each other. For example, it is possible to achievesuch a configuration that the hinge component 1 and the hinge component2 are detachable from each other, by protruding the input shaft 31 ofthe power generating device 3 from the through hole 1 c, and restrainingthe input shaft 31 of the power generating device 3 to the hingecomponent 2 by the screw 41. Accordingly, using the hinge device 10, itis possible to easily build the door including the stationary object 21and the movable object 22.

In the present disclosure, the hinge component 1, to which the housing30 of the power generating device 3 is fixed, is also referred to as a“first hinge component”, and the hinge component 2, to which the inputshaft 31 of the power generating device 3 is restrained, is alsoreferred to as a “second hinge component”. In addition, in the presentdisclosure, the “recess” includes a penetrating structure.

FIGS. 7 to 9 are perspective views illustrating the first to third stepsof attaching the hinge device 10 of FIG. 1, to the door including thestationary object 21 and the movable object 22. FIGS. 7 to 9 illustratea case where two hinge devices 10-1 and 10-2, configured in a mannersimilar to that of the hinge device 10 of FIGS. 3 to 6, are attached tothe door including the stationary object 21 and the movable object 22.The hinge device 10-1 includes hinge components 1-1 and 2-1 and a powergenerating device 3-1, and the hinge device 10-2 includes hingecomponents 1-2 and 2-2 and a power generating device 3-2.

As shown in FIG. 7, the hinge components 1-1 and 1-2 are fixed to thestationary object 21 with a plurality of screws 23. The hinge components2-1 and 2-2 are also fixed to the movable object 22 with a plurality ofscrews (not shown). Thereafter, the movable object 22 is attached to thestationary object 21, by engaging the hinge components 1-1 and 1-2 withthe hinge components 2-1 and 2-2, respectively, so that protrusions ofthe hinge components 1-1 and 1-2 are inserted into recesses of the hingecomponents 2-1 and 2-2, respectively. The hinge components 1-1 and 1-2,and the hinge components 2-1 and 2-2, each configured as shown in FIGS.3 to 6, are engaged with each other so as to be detachable from eachother. It is possible to easily build the door including the stationaryobject 21 and the movable object 22, by fixing the hinge components 1-1and 1-2 to the stationary object 21, fixing the hinge components 2-1 and2-2 to the movable object 22, and then, attaching the movable object 22to the stationary object 21.

Next, as shown in FIG. 8, the input shaft of the power generating device3-1 is restrained to the hinge component 2-1 by a screw 41-1, and theinput shaft of the power generating device 3-2 is restrained to thehinge component 2-2 by a screw 41-2. In this case, the weight of themovable object 22 is supported by the hinge components 1-1, 1-2, 2-1,and 2-2, and the stationary object 21. Since the weight of the movableobject 22 is not applied to the power generating devices 3-1 and 3-2, itis possible to reliably operate the power generating devices 3-1 and3-2, without applying an extra mechanical load to the power generatingdevices 3-1 and 3-2.

Thereafter, as shown in FIG. 9, when a user opens or closes the door,the movable object 22 rotates with respect to the stationary object 21about the reference axis of the hinge devices 10-1 and 10-2. At thistime, the power generating devices 3-1 and 3-2 generate electric powerby rotation of their input shafts.

Three or more hinge devices 10 may be used for attaching the movableobject 22 to the stationary object 21. In a case of using a plurality ofhinge devices for attaching the movable object 22 to the stationaryobject 21, a combination of hinge devices may be used, including: ahinge device 10 according to an embodiment of the present disclosure,provided with a power generating device 3; and a conventional hingedevice without a power generating device.

Referring again to FIG. 1, the rectifier circuit 11 rectifies theelectric power generated by the power generating device 3 of the hingedevice 10. Even if the power generator M1 is a DC generator, the powergenerator M1 rotates in reverse directions to generate a voltage ofreverse polarities, depending on whether the door is opened or closed.Therefore, rectification is required to store the generated electricpower in a capacitor or a secondary battery. The power storage circuit12 is provided with at least one capacitor that stores energy ofelectric power rectified by the rectifier circuit 11. The controllercircuit 13 controls discharging of the power storage circuit 12. Theload device 14 consumes electric power of the power storage circuit 12under control of the controller circuit 13. The load device 14 includes,for example, a lighting device and/or a communication device (wired orwireless).

In the power system of FIG. 1, a force exerted from a user's body isinputted to the power generating device 3 of the hinge device 10, viathe movable object 22 of the door. The stationary object 21 and themovable object 22 of the door, and the hinge component 1, the hingecomponent 2, and the power generating device 3 of the hinge device 10convert mechanical energy into electrical energy. The rectifier circuit11, the power storage circuit 12, and the controller circuit 13 convertelectrical energy into electrical energy. The output of the power systemof FIG. 1 is the work of the load device 14.

The rectifier circuit 11, the power storage circuit 12, the controllercircuit 13, and the load device 14 are disposed, for example, on astationary object 21, as shown in FIG. 1.

FIG. 10 is a circuit diagram illustrating the configuration of the powersystem according to the first embodiment. It is advantageous if a largeamount of electric power (energy) is extracted from very short movementof opening and closing the door only once. Therefore, in the powersystem of FIG. 10, two hinge devices, each provided with a powergenerating device, are installed at two locations on the door,respectively (see FIG. 9), and the power generators of these powergenerating devices are cascaded, i.e., connected in series, for use.Further, since the power generator rotates in reverse directions togenerate a voltage of reverse polarities, depending on whether the dooris opened or closed, voltage-doubling rectification can be used toeffectively extract the generated electric power.

The power system of FIG. 10 is provided with power generators M1 and M2included in the power generating devices of the two hinge devices,respectively. Referring to FIG. 10, the rectifier circuit 11 is providedwith four diodes D1 to D4. The power storage circuit 12 is provided withfour capacitors C1 to C4. The controller circuit 13 is provided withcapacitors C5 to C8, diodes D5 to D7, a coil L1, resistors R1 to R6, avariable resistor VR1, a transformer T1, and transistors TR1 to TR5. Inaddition, the power system of FIG. 10 is provided with a light emittingdiode 14 a and a wireless transmitter 14 b 1 as components correspondingto the load device 14 of FIG. 1. The wireless transmitter 14 b 1 iswirelessly-communicatively connected with a wireless receiver 14 b 2.

The diodes D1 and D2 and the capacitors C1 and C2 constitute avoltage-doubling rectifier circuit for voltage-doubling rectification ofvoltage generated by the power generator M1. Similarly, the diodes D3and D4 and the capacitors C3 and C4 constitute a voltage-doublingrectifier circuit for voltage-doubling rectification of voltagegenerated by the power generator M2. During a series of actionsincluding movements in reverse directions, such as opening and closingof a door, a voltage of reverse polarities is generated depending onwhether the door is opened or closed. By applying the voltage-doublingrectification to the generated voltage, instead of full-waverectification, it is possible to store twice voltage in a series ofactions, as compared to the case of the full-wave rectification. Thus,it is possible to operate subsequent-stage circuits of the power storagecircuit 12 at a high voltage, and therefore, improve the efficiency ofthe subsequent-stage circuits. On the other hand, according to thefull-wave rectification, substantially the same voltage is generatedregardless whether the door is opened or closed, and therefore, it isnot possible to increase the stored energy even if increasing durationof generation twice.

The capacitors C1 to C4 are, for example, electrolytic capacitors.

The output terminals of the power generators M1 and M2 are cascaded witheach other. For supporting a heavy movable object 22, typically, aplurality of hinge devices are used. When using two hinge devices, eachof these hinge devices may be provided with a power generating device.By cascading the capacitors C1 to C4 that are charged by voltagesgenerated by the power generators M1 and M2 of the power generatingdevices, the sum of voltages across the capacitors C1 to C4 is obtainedas the output voltage. Thus, it is possible to operate thesubsequent-stage circuits of the power storage circuit 12 at a highvoltage, and therefore, improve the efficiency of the subsequent-stagecircuits.

In the controller circuit 13, the capacitors C5 to C7, the diode D5, theresistors R1 to R6, the transformer T1, and the transistors TR2 to TR5constitute an inverter circuit 13 a. The inverter circuit 13 a operatesin a voltage-resonant mode, and performs soft switching (zero voltswitching). In addition, the capacitor C5, the resistor R1, the variableresistor VR1, and the transistors TR1 to TR3 constitute a voltagesetting circuit 13 b. The voltage setting circuit 13 b sets a voltagerange in which the power system operates, by the variable resistor VR1and the transistor TR1, in particular, sets a lower limit voltage of theoutput voltage of the power storage circuit 12. The controller circuit13 stops supplying electric power from the power storage circuit 12 tothe load device (light emitting diode 14 a), when the voltage across thecapacitors C1 to C4 of the power storage circuit 12 is equal to or lowerthan the lower limit voltage set by the voltage setting circuit 13 b. Inaddition, the capacitors C5 and C7, the resistors R1 to R3, R5, and R6,the transformer T1, and the transistors TR2, TR3, and TR5 constitute aconstant-current controller circuit 13 c. The constant-currentcontroller circuit 13 c supplies a constant current from the powerstorage circuit 12 to the load device (light emitting diode 14 a).

In general, when charging a capacitor from a completely empty state, itis charged at a theoretical efficiency of 50%. Further, when operatingthe load device while not generating electric power, the capacitorsshould store the minimum energy corresponding to electric power requiredto operate the load device. In addition, when operating the load device,the minimum voltage is needed enough to activate the transistors and thelike of the controller circuit. For these reasons, the controllercircuit 13 sets the lower limit voltage for the power storage circuit12. For example, assuming that generated voltage (induced electromotiveforce, speed electromotive force) per one power generator M1 is 12 (V).In this case, when the voltage V₁ across the capacitor C1 (withcapacitance C₁=0.01 F) reaches 10 V after generating electric power forone second, the energy of the capacitor C1 is: ½×C₁×V₁ ²=0.5 (J).Thereafter, when the controller circuit 13 operates the load device 14,and the voltage of the capacitor C1 decreases to the minimum voltage V₀₁(in this case, assuming 1.5 (V)), the remaining energy of the capacitorC1 is: ½×C₁×V₀₁ ²=0.011 (J). Accordingly, the available energy is about0.49 (J). Thus, by setting the lower limit voltage, it is possible tofully utilize the energy of the capacitors C1 to C4, and reliablyoperate the load device 14.

The light emitting diode 14 a can achieve the same illumination effectas that of an incandescent lamp and a fluorescent lamp, with smallerenergy and a smaller device as compared with those of an incandescentlamp and a fluorescent lamp. Accordingly, the light emitting diode 14 ais suitable for effectively utilizing limited energy in the power systemaccording to the embodiment of the present disclosure. In addition, inthe case of using the light emitting diode 14 a as the load device, whenopening and closing a door of a gate, an entrance, a corridor, or thelike, at night, it is possible to obtain an auxiliary illuminationeffect with brightness enough to guide around the door (e.g., around thefeet), for safe and assured movement at night. In addition, in the caseof using the light emitting diode 14 a as the load device, when asuspicious person tries to enter by opening and closing the door, it ispossible to warn the suspicious person and/or prevent his/her entry, ina manner similar to that of a sensor light. In addition, in the case ofusing the light emitting diode 14 a as the load device, when opening andclosing a door of a cabinet or warehouse (e.g., a cabinet under awashbasin, or outdoor warehouse) not connected to a commercial powersource, it is convenient to visually recognize the inside of the cabinetor warehouse for a certain period of time.

In the present disclosure, the light emitting diode 14 a is alsoreferred to as an “lighting device”.

In addition, the wireless transmitter 14 b 1 and the wireless receiver14 b 2 can be used to achieve a watching function for monitoring livingactivities of an elderly person or the like. For example, in a case ofusing the wireless transmitter 14 b 1 as the load device, byincorporating the hinge device into a toilet door, it is possible tonotify a predetermined person of information, such as the number oftimes by which a toilet is used, via wireless communication. Inparticular, this is effective in watching in a case where an elderlyperson and their family live apart. In addition, in a case of using thewireless transmitter 14 b 1 as the load device, when a suspicious persontries to enter by opening and closing a door of, e.g., a gate and/orentrance, it is possible to notify a predetermined person of the entryvia wireless communication, for assurance.

The power system according to the embodiment of the present disclosuremay be provided with a player device for voice guidance, a camera forcapturing digital images, and the like, as components corresponding tothe load device 14 of FIG. 1.

The power system according to the first embodiment may be provided withthree or more power generating devices.

In the present disclosure, the wireless transmitter 14 b 1 is alsoreferred to as a “communication device”. The power system according tothe embodiment, of the present disclosure may be provided with a wiredcommunication device, instead of and/or in addition to the wirelesstransmitter.

FIG. 11 is a schematic diagram illustrating operation of the powersystem according to the first embodiment. FIG. 11 illustrates a scene ofgeneration of electric power from energy obtained from a user's livingactivities, and utilization of the generated electric power. As shown inFIG. 11(a), for example, at night or in a dark place, the user pulls ahandle (door knob) of the movable object 22 to open a door. As shown inFIGS. 11(b) to 11(c), while the movable object 22 is moving to open thedoor, the power generating devices of the hinge devices 10-1 and 10-2generate electric power, and store the energy of the generated electricpower in the power storage circuit 12 (not shown in FIG. 11). Inaddition, as shown in FIG. 11(d), also while the movable object 22 ismoving to close the door, the power generating devices of the hingedevices 10-1 and 10-2 generate electric power, and store the energy ofthe generated electric power in the power storage circuit 12. As shownin FIG. 11(c), for example, 0.5 seconds after the user started to openthe door (that is, started to generate electric power), the controllercircuit 13 (not shown in FIG. 11) supplies the energy of the powerstorage circuit 12 to the load device 14, and turns on the load device14 (lighting device). As shown in FIG. 11(d), when the user closes thedoor and moves forward, the controller circuit 13 supplies the energy ofthe power storage circuit 12 to the load device 14, thus lighting theforward and guiding the user's feet. The load device 14 is kept lightingwhile the user is moving, e.g., for five seconds, and the user arrivesat the destination (e.g., the next door). As shown in FIG. 11(e), forexample, five seconds after starting to open the door, the controllercircuit 13 turns off the load device 14.

The controller circuit 13 may supply electric power from the powerstorage circuit 12 to the load device 14, simultaneously with the powergenerating action of the power generating device 3. In addition, thecontroller circuit 13 may supply electric power from the power storagecircuit 12 to the load device 14, after a predetermined time has elapsedfrom the power generating action of the power generating device 3. Inaddition, the controller circuit 13 may supply electric power from thepower storage circuit 12 to the load device 14, independently of thepower generating action of the power generating device 3. Accordingly,it is convenient and assured to operate the load device 14 at anymoment, including during, after, and before operation of the powergenerating device 3.

As described above, according to the power system of the firstembodiment, since the power generating device 3 is incorporated into thehinge device 10, it is possible to efficiently extract energy from theuser's living activities to generate electric power.

FIGS. 12 to 15 are perspective views illustrating the first to fourthsteps of assembling a hinge device 10A of a power system according to afirst modified embodiment of the first embodiment. The shape of thehinge component of the hinge device is not limited to that of FIGS. 3 to6. As shown in FIG. 12, a hinge component 1A has a protrusion 1Aa, arecess 1Ab, a through hole like, and a screw hole 1Ad corresponding tothe protrusion 1 a, the recess 1 b, the through hole 1 c, and the screwhole 1 d of the hinge component 1 of FIG. 3, respectively. A hingecomponent 2A has recesses 2Aa and 2Aaa, a screw hole 2Ab, and a screwhole 2Ac corresponding to the recess 2 a, the screw hole 2 b, and thescrew hole 2 c of the hinge component 2 of FIG. 3, respectively. Acylindrical portion of the hinge component 2A has the two recesses 2Aaand 2Aaa with different inner diameters. Thus, the weight of the hingecomponent 2A is applied to the hinge component 1A, at a position wherethe top of the cylindrical portion of the hinge component 1A is incontact with the top of the recess 2Aa of the hinge component 2A. Thescrew hole 2Ab penetrates the hinge component 2A from the outside of thehinge component 2A to the recess 2Aaa. As shown in FIGS. 13 to 15, thesubsequent assembly of the hinge device 10A is similar to the assemblyof the hinge device 10 described with reference to FIGS. 4 to 6.

FIG. 16 is a schematic diagram illustrating a configuration of a powersystem according to a second modified embodiment of the firstembodiment. Although the hinge device 10 of FIG. 16 is configured in amanner similar to that of the hinge device 10 of FIG. 1, the hingecomponent 1, to which the housing 30 of the power generating device 3 isfixed, is disposed above the hinge component 2, to which the input shaft31 of the power generating device 3 is restrained, and the hingecomponent 2 supports the hinge component 1. Thus, the hinge component 2may support the hinge component 1, instead of supporting the hingecomponent 2 by the hinge component 1. In addition, the hinge component1, to which the housing 30 of the power generating device 3 is fixed,may be fixed to the movable object 22, and the hinge component 2, towhich the input shaft 31 of the power generating device 3 is restrained,may be fixed to the stationary object 21.

FIG. 17 is a schematic diagram illustrating a configuration of a powersystem according to a third modified embodiment of the first embodiment.The rectifier circuit 11, the power storage circuit 12, the controllercircuit 13, and the load device 14 may be disposed on the movable object22, as shown in FIG. 17.

FIG. 18 is a schematic diagram illustrating a configuration of a powersystem according to a fourth modified embodiment of the firstembodiment. At least one of the rectifier circuit 11, the power storagecircuit 12, and the controller circuit 13 may be disposed on the hingecomponent 1, together with the power generating device 3. In the exampleof FIG. 18, the rectifier circuit 11 and the power storage circuit 12are provided in the recess (hollow) of the hinge component 1, togetherwith the power generating device 3, and the controller circuit 13 andthe load device 14 are disposed on the stationary object 21. Accordingto the configuration of FIG. 18, it is possible to simplify and improvethe appearance of the power system.

FIG. 19 is a schematic diagram illustrating a configuration of a powersystem according to a fifth modified embodiment of the first embodiment.At least one of the rectifier circuit 11, the power storage circuit 12,and the controller circuit 13 is not necessarily disposed in the recessof the hinge component 1, and may be disposed at other positions on thehinge component 1. In the example of FIG. 19, the rectifier circuit 11and the power storage circuit 12 are provided on the hinge component 1,and the controller circuit 13 and the load device 14 are disposed on thestationary object 21. Even when the circuit components can not bedisposed inside the hinge component 1, the circuit components can beprovided at any other locations in accordance with the user's usage andthe appearance.

FIG. 20 is a schematic diagram illustrating a configuration of a powersystem according to a sixth modified embodiment of the first embodiment.At least one of the rectifier circuit 11, the power storage circuit 12,and the controller circuit 13 may be disposed on the hinge component 2.In the example of FIG. 20, the rectifier circuit 11 and the powerstorage circuit 12 are provided on the hinge component 2, and thecontroller circuit 13 and the load device 14 are disposed on the movableobject 22. The hinge component 2 may be provided with a recess (hollow),and at least one of the rectifier circuit 11, the power storage circuit12, and the controller circuit 13 may be provided in the recess. Thus,the rectifier circuit 11, the power storage circuit 12, the controllercircuit 13, and the load device 14 can be disposed at desired locationsin accordance with the user's usage and the appearance.

The hinge device and the power system according to the first embodimentare characterized by the following configurations.

According to the hinge device of the first embodiment, the hinge device10 is provided with: the first hinge component 1 and the second hingecomponent 2 having the common reference axis, and the power generatingdevice 3. The first hinge component 1 and the second hinge component 2are engaged with each other, so as to be rotatable about the referenceaxis relative to each other, and so that one of the first hingecomponent I and the second hinge component 2 supports the other. Thepower generating device 3 is provided with the housing 30 and the inputshaft 31, and generates electric power by rotation of the input shaft31. The housing 30 of the power generating device 3 is fixed to thefirst hinge component 1, so that the input shaft 31 of the powergenerating device 3 is positioned on the reference axis. The input shaft31 of the power generating device 3 is restrained to the second hingecomponent 2 with respect to the direction of rotation about thereference axis, so that the input shaft 31 of the power generatingdevice 3 rotates by as much as rotation of the second hinge component 2when the second hinge component 2 rotates about the reference axis.

As a result, it is possible to provide the hinge device 10 provided withthe power generating device 3, the hinge device 10 being capable ofefficiently extracting energy from the user's living activities togenerate electric power.

According to the hinge device of the first embodiment, the first hingecomponent 1 may be provided with the through hole 1 c at the positionwhere the first hinge component 1 and the second hinge component 2 areengaged with each other, the through hole 1 c being formed so that theinput shaft 31 of the power generating device 3 protrudes from the firsthinge component 1 toward the second hinge component 2. The second hingecomponent 2 is formed to have the recess 2 a at the position where thefirst hinge component 1 and the second hinge component 2 are engagedwith each other, the recess 2 a accommodating the input shaft 31 of thepower generating device 3 protruding through the through hole 1 c.

As a result, by protruding the input shaft 31 of the power generatingdevice 3 from the through hole 1 c so as to be accommodated in therecess 2 a, the power generating device 3 can be incorporated in thehinge device 10, so that rotation of the hinge component 2 istransmitted to the power generating device 3 fixed to the first hingecomponent 1.

According to the hinge device of the first embodiment, the input shaft31 of the power generating device 3 may have the dent 32 on the sidesurface of the input shaft 31. The input shaft 31 of the powergenerating device 3 is restrained to the second hinge component 2 withrespect to the direction of rotation about the reference axis, by thescrew 41 extending from the outside of the second hinge component 2 tothe recess 2 a so as to penetrate the second hinge component 2 andcontact with the dent 32 in the recess 2 a.

As a result, the input shaft 31 of the power generating device 3 rotatesby as much as rotation of the second hinge component 2, when the secondhinge component 2 rotates about the reference axis. The screw 41 doesnot have to restrain the input shaft 31 of the power generating device 3to the hinge component 2 with respect to the longitudinal direction ofthe reference axis. Accordingly, since the weight of the hinge component2 is not applied to the power generating device 3 when the hingecomponent 1 supports the hinge component 2, it is possible to reliablyoperate the power generating device 3, without applying an extramechanical load to the power generating device 3.

According to the hinge device of the first embodiment, the first hingecomponent 1 and the second hinge component 2 may be engaged with eachother so as to be detachable from each other.

As a result, using the hinge device 10, it is possible to easily build,for example, a door including the stationary object 21 and the movableobject 22.

According to the hinge device of the first embodiment, the powergenerating device 3 may be provided with: the gear mechanism G1 thattransmits rotation of the input shaft 31 of the power generating device3 at the increasing gear ratio, and the power generator M1 thatgenerates electric power by rotation transmitted by the gear mechanismG1.

As a result, it is possible to efficiently generate electric power fromenergy obtained from the user's living activities, using the gearmechanism G1.

According to the power system of the first embodiment, the power systemis provided with the hinge device 10, the rectifier circuit 11, thepower storage circuit 12, the controller circuit 13, and the load device14. The rectifier circuit 11 rectifies the electric power generated bythe power generating device 3 of the hinge device 10. The power storagecircuit 12 stores the energy of electric power rectified by therectifier circuit 11. The controller circuit 13 controls discharging ofthe power storage circuit 12. The load device 14 consumes electric powerof the power storage circuit 12 under control of the controller circuit13.

As a result, using the rectifier circuit 11, the power storage circuit12, the controller circuit 13, and the load device 14, it is possible toeffectively utilize electric power generated from energy obtained fromthe user's living activities, according to usage of the load device 14.

According to the power system of the first embodiment, the powergenerating device 3, and at least one of the rectifier circuit 11, thepower storage circuit 12, and the controller circuit 13 may be providedon the first hinge component 1 of the hinge device 10.

As a result, it is possible to freely arrange the components of thepower system.

According to the power system of the first embodiment, at least one ofthe rectifier circuit 11, the power storage circuit 12, and thecontroller circuit 13 may be disposed on the second hinge component 2 ofthe hinge device 10.

As a result, it is possible to freely arrange the components of thepower system.

According to the power system of the first embodiment, one of the firsthinge component 1 and the second hinge component 2 of the hinge device10 may be fixed to the stationary object 21, and the other may be fixedto the movable object 22. The weight of the movable object 22 issupported by the first hinge component 1 and the second hinge component2, and the stationary object 21. When the movable object 22 rotates withrespect to the stationary object 21 about the reference axis of thehinge device 10, the power generating device 3 generates electric powerby rotation of the input shaft 31.

As a result, since the weight of the hinge component 2 and the movableobject 22 is not applied to the power generating device 3, it ispossible to reliably operate the power generating device 3, withoutapplying an extra mechanical load to the power generating device 3.

According to the power system of the first embodiment, at least one ofthe rectifier circuit 11, the power storage circuit 12, and thecontroller circuit 13 may be disposed on the stationary object 21.

As a result, it is possible to freely arrange the components of thepower system.

According to the power system of the first embodiment, at least one ofthe rectifier circuit 11, the power storage circuit 12, and thecontroller circuit 13 may be disposed on the movable object 22.

As a result, it is possible to freely arrange the components of thepower system.

According to the power system of the first embodiment, the powergeneration system may be provided with the plurality of power generatingdevices 3 cascaded with each other.

As a result, it is possible to generate a higher voltage or a largercurrent, as compared with a case where a single power generating device3 is provided.

According to the power system of the first embodiment, the power storagecircuit 12 may include the plurality of capacitors C1 to C4. Therectifier circuit 11 includes the voltage-doubling rectifier circuit.

As a result, it is possible to store twice voltage in a series ofactions, as compared to the case of the full-wave rectification.Accordingly, it is possible to operate the subsequent-stage circuits ofthe power storage circuit 12 at a high voltage, and therefore, improvethe efficiency of the subsequent-stage circuits.

According to the power system of the first embodiment, the controllercircuit 13 may supply electric power from the power storage circuit 12to the load device 14, simultaneously with power generating action ofthe power generating device 3, or after the predetermined time haselapsed from the power generating action of the power generating device3, or independently of the power generating action of the powergenerating device 3.

As a result, it is possible to operate the load device 14 at any moment,including during, after, and before operation of the power generatingdevice 3. Accordingly, it is possible to effectively utilize electricpower generated from energy obtained from the user's living activities,according to usage of the load device 14.

According to the power system of the first embodiment, the controllercircuit 13 may stop supplying electric power from the power storagecircuit 12 to the load device 14, when the voltage across the capacitorsC1 to C4 of the power storage circuit 12 is equal to or lower than thepredetermined lower limit voltage.

As a result, it is possible to fully utilize the energy of thecapacitors C1 to C4, and reliably operate the load device 14.

According to the power system of the first embodiment, the load device14 may include a lighting device.

As a result, the power system including the lighting device can beutilized for purposes of, e.g., lighting, warning to a suspiciousperson, and/or prevention of entry of a suspicious person.

According to the power system of the first embodiment, the load device14 may include the communication device.

As a result, the power system including the communication device can beutilized for purposes of, e.g., watching an elderly person and/ornotification of a suspicious person.

The hinge device according to the first embodiment can be applied to anystructure using the hinge device, such as doors, windows, gates, orlids. All the above-described advantageous effects can be obtained inthe opening/closing action of gates, revolving doors, and single doorsof general households, public facilities, or the like.

Second Embodiment

The shapes of hinge components of a hinge device are not limited tothose shown in FIGS. 3 to 6, and FIGS. 12 to 15. Hereinafter, hingedevices of power systems according to a second embodiment will bedescribed.

FIGS. 21 to 23 are perspective views illustrating first to third stepsof assembling a hinge device 10B of a power system according to thesecond embodiment. The hinge device 10B is provided with a hingecomponent 1B1, a hinge component 1B2, a hinge component 2B, and a powergenerating device 3.

As shown in FIG. 21, the hinge component 1B1 has a cylindrical portionand a planar portion coupled to each other. The cylindrical portion ofthe hinge component 1B1 has: a recess 1B1 a to be engaged with the hingecomponent 2B, and a recess 1B1 b accommodating the power generatingdevice 3. The cylindrical portion of the hinge component 1B1 is furtherprovided with a through hole 1B1 c at a position where the hingecomponent 1B1 and the hinge component 2B are engaged with each other,the through hole 1B1 c being formed so that the input shaft 31 of thepower generating device 3 protrudes from the hinge component 1B1 towardthe hinge component 2B. The planar portion of the hinge component 1B1has: a plurality of screw holes 1B1 d for fixing the hinge component 1B1to a stationary object with a plurality of screws, and a couplingportion 131 e including screw holes for coupling the hinge components1B1 and 1B2 to each other. The hinge component 1B2 also has acylindrical portion and a planar portion coupled to each other. Thecylindrical portion of the hinge component 1B2 has a recess 1B2 a to beengaged with the hinge component 2B. The planar portion of the hingecomponent 1B2 has: a plurality of screw holes 1B2 d for fixing the hingecomponent 1B2 to the stationary object with a plurality of screws, and acoupling portion 1B2 e including screw hales for coupling the hingecomponents 1B1 and 1B2 to each other. The hinge component 2B also has acylindrical portion and a planar portion coupled to each other. Thecylindrical portion of the hinge component 2B has a first end (lower endin FIG. 21) and a second end (upper end in FIG. 21) along a referenceaxis (indicated by line A-A′ in FIG. 21). The cylindrical portion of thehinge component 2B has: a protrusion 2Ba1 at the first end to be engagedwith the recess 1B1 a of the hinge component 1B1, and a protrusion 2Ba2at the second end to be engaged with the recess 1B2 a of the hingecomponent 1B2. The cylindrical portion of the hinge component 2B has arecess 2Bb at the first end to be engaged with the input shaft 31 of thepower generating device 3. The planar portion of the hinge component 2Bhas a plurality of screw holes 2Bc for fixing the hinge component 2B toa movable object with a plurality of screws.

The input shaft 31 of the power generating device 3 has a protrusion 34of some shape at a tip thereof, instead of the dent 32 of FIG. 2, sothat the input shaft 31 is restrained to the hinge component 2B withrespect to the direction of rotation about the reference axis. In theexample of FIG. 21, the input shaft 31 of the power generating device 3has a gear-shaped protrusion 34. The recess 2Bb of the hinge component2B is shaped complementary to the protrusion 34 of the power generatingdevice 3 as seen from a point on the reference axis.

As shown in FIG. 22, the hinge components 1B1 and 1B2 and the hingecomponent 2B are engaged with each other, so as to be rotatable about acommon reference axis relative to each other, and so that one of thehinge components 1B1 and 1B2 and the hinge component 2B supports theother. Since the recess 1B1 a of the hinge component 1B1 has an innercylindrical surface, and the protrusion 2Ba1 of the hinge component 2Bhas an outer cylindrical surface, the hinge component 1B1 and the hingecomponent 2B are engaged with each other so as to be rotatable relativeto each other. Similarly, since the recess 1B2 a of the hinge component1B2 has an inner cylindrical surface, and the protrusion 2Ba2 of thehinge component 2B has an outer cylindrical surface, the hinge component1B2 and the hinge component 2B are engaged with each other so as to berotatable relative to each other. In addition, in the example of FIG.22, the hinge component 2B is disposed between the hinge components 1B1and 1B2, and the hinge components 1B1 and 1B2 support the hingecomponent 2B. The hinge components 1B1 and 1B2 are coupled to each otherat the coupling portions 1B1 e and 1B2 e with screws 1B3.

Except for the position where the hinge components 1B1 and 1B2 and thehinge component 2B are engaged with each other so as to be rotatablerelative to each other (i.e., the recess 1B1 a of the hinge component1B1, the recess 1B2 a of the hinge component 1B2, and the protrusions2Ba1 and 2Ba2 of the hinge component 2B), the outer surfaces of thehinge components 1B1 and 1B2 and the hinge component 2B may not becylindrically shaped, but may be shaped as triangular prisms,quadrangular prisms, other polygonal prisms, other polyhedrons.

As shown in FIG. 23, the power generating device 3 is inserted into therecess 1B1 b of the hinge component 1B1. The housing 30 of the powergenerating device 3 is fixed to the hinge component 1B1 with anadhesive, a screw (not shown) or the like, so that the input shaft 31 ofthe power generating device 3 is positioned on the reference axis. Therecess 2Bb of the hinge component 2B accommodates the protrusion 34 atthe tip of the input shaft 31 of the power generating device 3, theprotrusion 34 protruding through the through hole 1B1 c. Since theprotrusion 34 of the power generating device 3 and the recess 2Bb of thehinge component 2B are shaped complementary to each other, the inputshaft 31 of the power generating device 3 is restrained to the hingecomponent 2B with respect to the direction of rotation about thereference axis. Accordingly, when the hinge component 2B rotates aboutthe reference axis, the input shaft 31 of the power generating device 3rotates by as much as rotation of the hinge component 2B.

The hinge device 10B is made by engaging the hinge components 1B1 and1B2 and the hinge component 2B with each other, fixing the housing 30 ofthe power generating device 3 to the hinge component 1B1, restrainingthe input shaft 31 of the power generating device 3 to the hingecomponent 2B, and coupling the hinge components 1B1 and 1B2 to eachother with a screw 1B3.

Since the hinge device 10B is configured as shown in FIGS. 21 to 23, thepower generating device 3 is incorporated in the hinge device 10B. Inthe hinge device 10B, the input shaft 31 of the power generating device3 protrudes from the through hole 1B1 c, and the input shaft 31 of thepower generating device 3 is restrained to the hinge component 2B by theprotrusion 34 of the power generating device 3 and the recess 2Bb of thehinge component 2B, being shaped complementary to each other.Accordingly, rotation of the hinge component 2B can be transmitted tothe power generating device 3 accommodated in the recess 1B1 b of thehinge component 1B1. Thus, it is possible to achieve such aconfiguration that the power generating device 3 is incorporated in thehinge device 10B. Since the power generating device 3 is incorporated inthe hinge device 10B, it is possible to provide the hinge device 10Bhaving a good appearance.

In addition, since the hinge components 1B1 and 1B2 support the hingecomponent 2B, the weight of the hinge component 2B is not applied to thepower generating device 3. The protrusion 34 of the power generatingdevice 3 and the recess 2Bb of the hinge component 2B, being shapedcomplementary to each other, do not have to restrain the input shaft 31of the power generating device 3 to the hinge component 2B with respectto the longitudinal direction of the reference axis, but restrain theinput shaft 31 to the hinge component 2B with respect to at least thedirection of rotational about the reference axis. Accordingly, it ispossible to achieve such a configuration that the weight of the hingecomponent 2B (and a movable object 22 described below) is not applied tothe power generating device 3, while the input shaft 31 of the powergenerating device 3 protrudes from the through hole 1B1 c, and the inputshaft 31 of the power generating device 3 is restrained to the hingecomponent 2B by the protrusion 34 of the power generating device 3 andthe recess 2Bb of the hinge component 2B, being shaped complementary toeach other. Since the weight of the hinge component 2B (and the movableobject 22B) is not applied to the power generating device 3, it ispossible to reliably operate the power generating device 3, withoutapplying an extra mechanical load to the power generating device 3.

In addition, the hinge components 1B1 and 1B2 and the hinge component 2Bhaving the configurations of FIGS. 21 to 23 are integrally configured soas to be rotatable with respect to each other. Accordingly, using thehinge device 10B, it is possible to easily build a door including astationary object and a movable object.

In the present disclosure, the hinge components 1B1 and 1B2 are alsoreferred to as “first hinge component”, and the hinge component 2B isalso referred to as a “second hinge component”. In addition, in thepresent disclosure, the hinge component 1B1 is also referred to as a“first portion of the first hinge component”, and the hinge component1B2 is also referred to as a “second portion of the first hingecomponent”.

FIGS. 24 to 26 are perspective views illustrating first to third stepsof attaching the hinge device 10B of FIG. 18, to a door including astationary object 21B and a movable object 22B. As shown in FIG. 24, thestationary object 21B has a recess 21Ba for accommodating the hingedevice 10B. The hinge components 1B1 and 1B2 are fixed to the stationaryobject 21B in the recess 21Ba thereof with a plurality of screws (notshown). Similarly, the hinge component 2B is fixed to the movable object22B with a plurality of screws 23. As shown in FIG. 25, after the hingecomponents 1B1 and 1B2 are fixed to the stationary object 21B, therecess 21Ba of the stationary object 21B may be covered with covers21Bb. Thereafter, as shown in FIG. 26, when the user opens or closes thedoor, the movable object 22B rotates with respect to the stationaryobject 21B about the reference axis of the hinge device 10B. At thistime, the power generating device 3 generates electric power by rotationof the input shaft.

The protrusion 34 of the power generating device 3 and the recess 2Bb ofthe hinge component 2B, being shaped complementary to each other, arenot limited to be shaped like gears, but may be shaped in any othershape, as long as the input shaft 31 of the power generating device 3can be restrained to the hinge component 2B.

FIG. 27 is a perspective view illustrating configurations of a powergenerating device 3 and a hinge component 2B according to a firstmodified embodiment of the second embodiment. The input shaft 31 of thepower generating device 3 may have a triangular protrusion 34A, and thehinge component 2B may have a complementary triangular recess 2BbA.

FIG. 28 is a perspective view illustrating configurations of a powergenerating device 3 and a hinge component 2B according to a secondmodified embodiment of the second embodiment. The input shaft 31 of thepower generating device 3 may have a quadrangular protrusion 34B, andthe hinge component 2B may have a complementary quadrangular recess2BbB.

FIG. 29 is a perspective view illustrating configurations of a powergenerating device 3 and a hinge component 2B according to a thirdmodified embodiment of the second embodiment. The input shaft 31 of thepower generating device 3 may have a cross-shaped protrusion 34C, andthe hinge component 2B may have a complementary cross-shaped recess2BbC.

In addition, the input shaft 31 of the power generating device 3 mayhave a recess of some shape and the recess 2Bb of the hinge component 2Bmay have a protrusion of a complementary shape.

The hinge devices according to the second embodiment are characterizedby the following configurations.

According to the hinge device of the second embodiment, the input shaftof the power generating device 3 and the recess of the hinge component2B may be shaped complementary to each other as seen from the point onthe reference axis.

As a result, the input shaft 31 of the power generating device 3 rotatesby as much as rotation of the second hinge component 2B when the secondhinge component 2B rotates about the reference axis. The protrusion 34of the power generating device 3 and the recess 2Bb of the hingecomponent 2B, being shaped complementary to each other, do not have torestrain the input shaft 31 of the power generating device 3 to thehinge component 2B with respect to the longitudinal direction of thereference axis. Accordingly, when the hinge components 1B1 and 1B12support the hinge component 2B, the weight of the hinge component 2B isnot applied to the power generating device 3. Therefore, it is possibleto reliably operate the power generating device 3, without applying anextra mechanical load to the power generating device 3.

According to the hinge device of the second embodiment, the hingecomponents 1B1 and 1B2 may include the first portion (hinge component1B1) and the second portion (hinge component 1B2). The hinge component2B has the first and second ends along the reference axis, and the hingecomponent 2B is engaged with the hinge component 1B1 at the first end,and engaged with the hinge component 1B2 at the second end. The hingecomponents 1B1 and 1B2 are coupled to each other.

As a result, using the hinge device 10B, it is possible to easily build,for example, a door including a stationary object and a movable object.

According to the second embodiment, additionally or alternatively, thepower generating device 3 may be provided in the hinge component 1B2.

The first and second embodiments may be combined with each other. Forexample, in the first embodiment, the tip of the input shaft 31 of thepower generating device 3 and the recess 2 a of the hinge component 2may be shaped complementary to each other, instead of the dent 32 andthe screw 41. In addition, in the second embodiment, the input shaft 31of the power generating device 3 may be restrained to the hingecomponent 2B by a screw 41 penetrating the hinge component 2B. Variousmethods for restraining the input shaft 31 of the power generatingdevice 3 to the hinge component 2B can be selected according to usageand size. In addition, in the first embodiment, the hinge component 1may have a recess to be engaged with the hinge component 2, and thehinge component 2 may have a protrusion to be engaged with the hingecomponent 1. In addition, in the second embodiment, at least one of thehinge components 1B1 and 1B2 may have a protrusion to be engaged withthe hinge component 2B, and the hinge component 2B may have acorresponding recess.

Third Embodiment

If the capacitors of the power storage circuit 12 have smallcapacitance, the battery is fully charged in a moment, and part of thegenerated electric power may be wasted. In addition, if the capacitorsof the power storage circuit 12 have large capacitance, their size andcost increase. For a power generation system provided with the powergenerating device 3, the rectifier circuit 11, and the power storagecircuit 12, it is an important issue to determine the capacitance of thecapacitors of the power storage circuit 12 in consideration of variousrequirements. Accordingly, it is required to easily determine theoptimal or nearly optimal capacitance of capacitors, and to provide apower system provided with such capacitors.

According to the third embodiment, a power system is provided, the powersystem being provided with capacitors having capacitance determined soas to reduce waste in generated electric power, without excessivelyincreased size and cost.

In power systems according to embodiments of the present disclosure, itwould be advantageous that the power generating device 3 can generate avoltage as large as possible, when mechanical energy is inputted at asmall angular velocity as slow as possible. Accordingly, hereinafter, wewill illustrate a case of using a combination of a gear mechanism G1having a high increasing gear ratio, and a power generator M1 having ahigh rated output voltage.

Hereinafter, we will describe a simulation performed by the presentinventor.

In the simulation, a planetary gear mechanism having a decreasing gearratio of 1/G=1/242, and a micromotor having a rated input voltageV_(m)=24 (V) were combined, and the combination of the planetary gearmechanism and the micromotor was used as the power generating device 3.In this case, it is necessary to obtain a large speed electromotiveforce (voltage at output terminals of the power generator), when theinput shaft is rotated slowly at a small angular velocity. Where, “Nma”(rpm) denotes the rotational speed of the output shaft of the motor whenno load is applied, and “Nda” (rpm) denotes the rotational speed of theoutput shaft of the gear mechanism when no load is applied. When avoltage 24 (V) is applied to the motor, the no-load rotational speed Nda(rpm) is 28 (rpm). Under such conditions, we obtain design valuesnecessary for using this motor as a power generator.

At first, we describe calculation of the counter electromotive voltageconstant Ked (V/(rad/s)). The counter electromotive voltage constant Kedis an important indicator indicating the voltage across the outputterminals of the power generating device 3, with respect to therotational speed of the input shaft of the power generating device 3. Asthe counter electromotive voltage constant Ked becomes larger, a largervoltage output can be obtained from slow rotation. The SI units(International System of Units) are used throughout the presentdisclosure. By converting the rotational speed Nda=28 (rpm) of theoutput shaft of the gear mechanism, when no load is applied, into SIunits, the rotational angular velocity coda (rad/s) is obtained asfollows.

ωda=28×2×π/60=2.932 (rad/s)

Accordingly, the counter electromotive voltage constant Ked of the gearmechanism and the motor is obtained as follows.

Ked=24/(28×2×π/60)

=24/2.932

=8.185 (V/(rad/s))

For reference, the counter electromotive voltage constant Kem(V/(rad/s)) of only the motor, not including the gear mechanism, isobtained as follows.

Kem=Ked/G

=24/(28×2×π/60)/242

=0.03382 (V/(rad/s))

Next, we will describe calculation of the output voltage E_(m) (V) ofthe power generating device 3.

In a case where the above-described motor and gear mechanism are used asthe power generating device 3, the gear mechanism has an increasing gearratio G=242. In this case, rotational torque Td is applied to the inputshaft of the gear mechanism. The corresponding rotational angularvelocity cod (rad/s) is obtained from the duration “t” (s) and therotational angle θd_(d) (degree) of the single opening or closing actionof the door. Suppose t=1 (s) and θd_(d)=90 (degrees), then,θd=90×π/180=π/2 (rad), and therefore, ωd (rad/s) is obtained as follows.

ωd=(π/2)/1=1.571 (rad/s)

For reference, the rotational angular velocity ωm (rad/s) of only themotor, not including the gear mechanism, is obtained as follows.

ωm=G×ωd=380.2 (rad/s)

In this case, since Ked=8.185 (V/(rad/s)), the output voltage E_(m) (V)of the power generating device 3 is obtained as follows.

E _(m)(V)=Ked×ωd=8.185×1.571=12.86

That is, in a case where the door is opened at a constant speed of 90degrees per second, the voltage generated at the output terminals of thepower generating device 3 (speed electromotive force) is 12.86 (V).

Next, we will describe operations of the rectifier circuit 11 and thepower storage circuit 12. Hereinafter, it is assumed that the rectifiercircuit 11 and the power storage circuit 12 are configured as shown inFIG. 10.

FIG. 30 is a schematic diagram for illustrating operations of the fourcapacitors C1 to C4 in the power system according to the thirdembodiment. As mentioned above, voltage-doubling rectification isapplied to voltage generated by the two power generators M1 and M2, andthe capacitors C1 to C4 to be charged with voltage generated by thepower generators M1 and M2 are cascaded with each other. In this case,we will investigate electrical energy to be stored by opening and thenclosing the door only once.

“E_(m1)” and “E_(m2)” denote output voltages of the power generators M1and M2, respectively. “R_(m1)” and “R_(m2)” denote resistances ofwinding of the power generators M1 and M2, respectively. “C₁” to “C₄”denote capacitances of the capacitors C1 to C4, respectively. “V₁” to“V₄” denote voltages stored in the capacitors C1 to C4, respectively.“V_(o)” denotes a voltage across the four cascaded capacitors C1 to C4.In this case, each of waveforms of the voltages E_(m1) and E_(m2)represents a rectangular wave (AC voltage waveform) generated from theopening and closing actions of the door. The waveform of the voltageV_(o) indicates the change over time in the stored voltage, depending ontime constants of the resistances R_(m1) and R_(m2) and the capacitancesC₁ to C₄. In the embodiment, the energy stored in the capacitors C1 toC4 is not completely consumed until the voltage across the capacitors C1to C4 becomes zero, but supplying electric power from the power storagecircuit 12 to the load device 14 is stopped when the voltage of onecapacitor drops to a predetermined threshold voltage V₀₁ (V).Accordingly, when charging one capacitor, a state of the lower limitvoltage (initial voltage) V₀₁ (V), and a state of the voltage V₁ at theend of the door opening/closing action are repeated.

FIG. 31 is a schematic diagram for illustrating operation of onecapacitor. C1 in the power system according to the third embodiment.Referring to FIG. 31, we analyze the operation of storing electric powergenerated by one power generator M1 when opening the door, in onecapacitor C1. In the embodiment, this operation serves as a buildingblock, and when the door is opened and closed only once in the electricpower system including two power generators M1 and M2, a stored energyfour times that of the building block operation is obtained.

Referring to FIG. 31, the voltage V₁ (V) across the capacitor C1 isobtained as follows.

V ₁ =V ₀₁+(E _(m1) −V ₀₁)(1−e ^(−t/τ) ¹ )  [Mathematical Expression 1]

Where, “V₀₁” (V) denotes the lower limit voltage of the capacitor C1, asdescribed above. “τ₁” denotes a time constant τ₁=C₁R_(m1), based on thecapacitance C₁ of the capacitor C1, and the resistance R_(m1) of thepower generator M1.

Accordingly, the maximum energy W_(E1M) (J) to be stored in thecapacitor C1 is obtained as follows.

W_(E1M)=½C₁V₁ ²  [Mathematical Expression 2]

The available energy W_(E1) (J) to be supplied from the capacitor C1 tothe load device 14 is obtained as follows.

W _(E1)=½C ₁ V ₁ ²−½C ₁ V ₀₁ ²=½C ₁(V ₁ ² −V ₀₁ ²)  [MathematicalExpression 3]

For exemplary calculation, it is assumed that V₀₁=1.5 (V), C₁=0.01 (F),R_(m1)=60 (Ω), t=1 (s), and E_(m1)=12.86 (V). In this case, the voltageacross the capacitor C1 is: V₁=10.712 (V). The maximum energy to bestored in the capacitor C1 is: W_(E1M)=0.5738 (J). The available energyto be supplied from the capacitor C1 to the load device 14 is:W_(E1)=0.5625 (J).

Next, we calculate the energy to he stored in all the capacitors C1 toC4 of FIG. 30. In this case, conditions V₁=V₂=V₃=V₄ and V₀₁=V₀₂=V₀₃=V₀₄are set. Then, the following equations are obtained.

V _(o) =V ₁ +V ₂ +V ₃ +V ₄=4V ₁=42.8 (V)

V _(o1) =V ₀₁ +V ₀₂ +V ₀₃ +V ₀₄=4V ₁=6 (V)

Conditions C₁=C₂=C₃=C₄ are set. The total capacitance C_(o) of thecapacitors C1 to C4 is given by C_(o)=(¼)C₁. The total stored energyW_(EM) (J) of the capacitors C1 to C4 is obtained as follows.

W _(EM)=4×W _(E1M)=2C ₁ V ₁ ²=2.295 (J)

The available energy W_(EE) (J) of the capacitors C1 to C4 is obtainedas follows.

$W_{EE} = {{\frac{1}{2}{C_{o}\left( {V_{o}^{2} - V_{o\; 1}^{2}} \right)}} = {{\frac{1}{2} \cdot \left( {\frac{1}{4}C_{1}} \right) \cdot \left( {\left( {4\; V_{1}} \right)^{2} - \left( {4\; V_{01}} \right)^{2}} \right)} = {{{\frac{1}{2} \cdot \left( {\frac{1}{4}C_{1}} \right) \cdot 16}\left( {V_{1}^{2} - V_{01}^{2}} \right)} = {2\; {C_{1}\left( {V_{1}^{2} - V_{01}^{2}} \right)}}}}}$

The available energy W_(EE) is, for example, 2.25 (J).

In addition, the average output electric power P_(EM) (W) from the powergenerators M1 and M2 is obtained as follows.

P _(EM) =W _(EM)/(2t)=2.295/(2×1)=1.147 (W)

According to the example as described above, we confirmed that the powersystem according to the embodiment can generate electric power exceeding1 (W) and 1 (J).

Next, we calculate characteristics of the available energy of thecapacitors C1 to C4, when changing some parameters of the mathematicalexpressions as described above.

FIG. 32 is a graph showing characteristics of available energy tocapacitance of a power system according to a first implementationexample of the third embodiment. FIG. 33 is a graph showingcharacteristics of available energy to capacitance of a power systemaccording to a second implementation example of the third embodiment.

In the implementation examples of FIGS. 32 and 33, the following commonparameters were set.

Duration during which door is opened once: t=1 (s)

Duration during which door is closed once: t=1 (s)

Angie through which door is opened and closed: 90 (degrees)

Motor's rated input voltage: V_(m)=24 (V)

Motor's winding resistance: R_(m1)=R_(m2)=60 (Ω)

Capacitances of capacitors C1 to C4: variable

Lower limit voltage of capacitors C1 to C4: V₀₁=V₀₂=V₀₃=V₀₄=1.5 (V)

In the implementation example of FIG. 32, the following parameters wereset.

Increasing gear ratio of gear mechanism: G=242

Counter electromotive voltage constant of each power generating device:Ked=8.185 (V/(rad/s))

Speed electromotive force: E_(m1)=E_(m2)=12.857 (V)

In the implementation example of FIG. 33, the following parameters wereset.

Increasing gear ratio of gear mechanism: G=107

Counter electromotive voltage constant of each power generating device:Ked=3.62 (V/(rad/s))

Speed electromotive force: E_(m1)=E_(m2)=5.69 (V)

Under such conditions, the characteristics of available energy tocapacitance were calculated as shown in FIGS. 32 and 33, thecharacteristics being calculated as an upper limit available energy tobe stored in the capacitors C1 to C4, with respect to the totalcapacitance of the capacitors C1 to C4.

Referring to FIGS. 32 and 33, it can be seen that even when increasingthe capacitances of the capacitors C1 to C4, the available energyreaches the upper limit at a certain capacitance. In addition, in thecase of FIG. 32, it can be clearly seen that the available energy has apeak value. Comparing FIGS. 32 and 33 with each other, the availableenergy reaches the maximum at the capacitance of about 15 mF. Theexistence of this maximum can be explained by the fact that the outputvoltages E_(m1) and E_(m1) of the power generating devices are the samein cases of FIGS. 32 and 33, and the fact that the windings of the powergenerators M1 and M2 have resistances R_(m1) and R_(m2), respectively.According to such characteristics, it can be seen that the availableenergy reaches the peak value at the capacitance of about 15 mF.Therefore, it can be seen that even when using capacitors having largercapacitances, their size and cost adversely increase. The capacitancesof the capacitors C1 to C4 are gradually increased, and then, when theavailable energy approaches the peak value, the correspondingcapacitance Cp is determined as the energy-maximizing capacitance.According to the power system of the embodiment of the presentdisclosure, it can be seen that when selecting the energy-maximizingcapacitance Cp as a design value, it is possible to achieve the maximumor nearly maximum performance with small size and low cost.

The capacitances of the capacitors C1 to C4 are not necessarily strictlyidentical to the peak available energy. For example, in a case where theavailable energy has a clear peak value as shown in FIG. 32, acapacitance may be selected from a range of capacitance corresponding to80% (20% lower) to 90% (10% lower) of the strict peak available energybased on experiment. The range of capacitance is from a capacitance Cps1lower than the energy-maximizing capacitance Cp, to a capacitance Cps2higher than the energy-maximizing capacitance Cp, the energy-maximizingcapacitance Cp corresponding to the strict peak available energy. Inthis case, the reason for selecting the capacitances Cps1 and Cps2corresponding to 80% to 90% of the peak available energy is to considerthe range of variations of typical components.

In addition, as shown in FIG. 33, after the available energy has reachedthe strict peak value based on experiment, the magnitude of theavailable energy may not much change from the peak value, even whenfurther increasing the capacitances of the capacitors C1 to C4. In thiscase, when the energy-maximizing capacitance Cp corresponds to thestrict peak available energy, a capacitance may be selected from a rangeof capacitance, having a lower limit capacitance Cps1 corresponding toan available energy between 80% (20% lower) to 90% (10% lower) of thepeak available energy (capacitance lower than the energy-maximizingcapacitance Cp), and an upper limit capacitance Cp2 twice theenergy-maximizing capacitance Cp. In this case, the reason for settingthe upper limit twice the energy-maximizing capacitance Cp is that thecapacitors' size is nearly doubled and their cost also increasesaccordingly, and it is considered that a capacitance up to twice theenergy-maximizing capacitance Cp is acceptable as a small andinexpensive power system.

Thus, according to the power system of the third embodiment, sinceelectric power can be stored in capacitors capable of substantiallymaximizing the stored energy, it is possible to optimize the use ofgenerated electric power for operating a load device. In addition,according to the power system of the third embodiment, since the maximumenergy can be stored and utilized while using the smallest and the mostinexpensive capacitors, it is possible to provide a small andinexpensive power generation system.

In the above description, we calculated the characteristics of availableenergy to capacitance, indicating the upper limit available energy to bestored in the power storage circuit 12, with respect to the capacitanceof the power storage circuit 12. However, instead of the characteristicsof available energy to capacitance, the characteristics of energy tocapacitance may be calculated, indicating an upper limit energy to bestored in the power storage circuit 12, with respect to the capacitanceof the power storage circuit 12. Also in the case of calculating thecharacteristics of energy to capacitance, a capacitance equal to or nearthe energy-maximizing capacitance can be set as the capacitance of thepower storage circuit 12, the energy-maximizing capacitance indicatingthe capacitance maximizing the upper limit energy in the characteristicsof energy to capacitance.

The power generation systems and the power systems according to thethird embodiment are characterized by the following configurations.

According to the power generation system of the third embodiment, thepower generation system is provided with: at least one power generatingdevice 3 that generates electric power by rotation of the input shaft31; and the power storage circuit 12 including at least one capacitor C1to C4, that stores the energy of the electric power generated by thepower generating device 3. The power storage circuit 12 has acapacitance equal to or near the energy-maximizing capacitance, theenergy-maximizing capacitance indicating a capacitance maximizing theupper limit energy in the characteristics of energy to capacitance, thecharacteristics being calculated as the upper limit energy to be storedin the power storage circuit 12, with respect to the capacitance of thepower storage circuit 12. The characteristics of energy to capacitanceare calculated based on: the capacitance of the power storage circuit12, the electromotive force of the power generating device 3, theinternal resistance of the power generating device 3, and the durationof one power generating action of the power generating device 3.

As a result, it is possible to provide a power generation systemprovided with capacitors having capacitance determined so as to reducewaste in generated electric power, without excessively increasing sizeand cost.

According to the power generation system of the third embodiment, thepower storage circuit 12 may have a capacitance within a range ofcapacitance corresponding to a range of energy whose upper limit isequal to or greater than a predetermined value near the maximum energyin the characteristics of energy to capacitance.

As a result, it is possible to maximize or nearly maximize the upperenergy in the characteristics of energy to capacitance, while usingsmall and inexpensive capacitors.

According to the power generation system of the third embodiment, thepower storage circuit 12 may have a capacitance within a range ofcapacitance corresponding to a range of energy whose upper limit isequal to or greater than a predetermined value between 80% to 90% of themaximum energy in the characteristics of energy to capacitance.

As a result, in consideration of the range of variations of typicalcomponents, it is possible to nearly maximize the upper limit energy inthe characteristics of energy to capacitance, while using small andinexpensive capacitors.

According to the power generation system of the third embodiment, thepower storage circuit 12 may have a capacitance within a range ofcapacitance corresponding to a range of energy whose upper limit isequal to or greater than a predetermined value near the maximum energyin the characteristics of energy to capacitance, the range ofcapacitance having a lower limit capacitance smaller than theenergy-maximizing capacitance, and an upper limit capacitance obtainedby multiplying the energy-maximizing capacitance by a factor larger thanone.

As a result, it is possible to nearly maximize the upper limit energy inthe characteristics of energy to capacitance, while using small andinexpensive capacitors, i.e., keeping increases in the capacitors' sizeand cost small to an acceptable extent.

According to the power generation system of the third embodiment, thepower storage circuit 12 may have a capacitance within a range ofcapacitance corresponding to a range of energy whose upper limit isequal to or greater than a predetermined value between 80% to 90% of themaximum energy in the characteristics of energy to capacitance, therange of capacitance having a lower limit capacitance smaller than theenergy-maximizing capacitance, and an upper limit capacitance twice theenergy-maximizing capacitance.

As a result, it is possible to maximize or nearly maximize the upperlimit energy in the characteristics of energy to capacitance, whileusing small and inexpensive capacitors, i.e., keeping increases in thecapacitors' size and cost small to an acceptable extent.

According to the power generation system of the third embodiment, thecharacteristics of energy to capacitance may be obtained by:

W _(E1M)=½C ₁(V ₀₁+(E _(m1) −V ₀₁)(1−e ^(−t/τ) ¹ ))²  [MathematicalExpression 5]

where, “C₁” denotes the capacitance of the capacitor C1 of the powerstorage circuit 12; “V₀₁” denotes the lower limit voltage of thecapacitor C1; “E_(m1)” denotes the electromotive force of the powergenerating device 3; “t” denotes the duration of one power generatingaction of the power generating device 3; and “τ₁” denotes the timeconstant, based on the capacitance C₁ of the capacitor C1, and theinternal resistance of the power generating device 3.

As a result, it is possible to calculate the energy-maximizingcapacitance based on the characteristics of energy to capacitance.

According to the power generation system of the third embodiment, thepower generating device 3 may be provided with: the gear mechanism G1that transmits rotation of the input shaft 31 of the power generatingdevice 3 at the increasing gear ratio; and the power generator M1 thatgenerates electric power by rotation transmitted by the gear mechanismG1.

As a result, it is possible to efficiently generate electric power fromenergy obtained from the user's living activities, using the gearmechanism G1.

According to the power generation system of the third embodiment, thepower generation system may be provided with the plurality of powergenerating devices 3 cascaded with each other.

As a result, it is possible to generate a higher voltage or a largercurrent, as compared with a case where a single power generating device3 is provided.

According to the power generation system of the third embodiment, thepower generation system may be further provided with the rectifiercircuit 11 that rectifies the electric power generated by the powergenerating device 3. The power storage circuit 12 stores energy of theelectric power generated by the power generating device 3 and rectifiedby the rectifier circuit 11.

As a result, it is possible to generate AC power by the power generatingdevice 3, and store the energy of the AC power in the power storagecircuit 12.

According to the power generation system of the third embodiment, thepower storage circuit 12 may include the plurality of capacitors C1 toC4, The rectifier circuit 11 includes the voltage-doubling rectifiercircuit.

As a result, it is possible to store twice voltage in a series ofactions, as compared to the case of the full-wave rectification.Accordingly, it is possible to operate the subsequent-stage circuits ofthe power storage circuit 12 at a high voltage, and therefore, improvethe efficiency of the subsequent-stage circuits.

According to the power generation system of the third embodiment, thepower generation system may be further provided with the hinge device 10provided with the first hinge component 1 and the second hinge component2 having the common reference axis. The first hinge component 1 and thesecond hinge component 2 are engaged with each other, so as to berotatable about the reference axis relative to each other, and so thatone of the first hinge component 1 and the second hinge component 2supports the other. The housing 30 of the power generating device 3 isfixed to the first hinge component 1, so that the input shaft 31 of thepower generating device 3 is positioned on the reference axis. The inputshaft 31 of the power generating device 3 is restrained to the secondhinge component 2 with respect to the direction of rotation about thereference axis, so that the input shaft 31 of the power generatingdevice 3 rotates by as much as rotation of the second hinge component 2when the second hinge component 2 rotates about the reference axis.

As a result, it is possible to provide the hinge device 10 provided withthe power generating device 3, the hinge device 10 being capable ofefficiently extracting energy from the user's living activities togenerate electric power.

According to the power system of the third embodiment, the power systemis provided with: the power generation system; the controller circuit 13that controls discharging of the power storage circuit 12 of the powergeneration system; and the load device 14 that consumes the electricpower of the power storage circuit 12 under control of the controllercircuit 13.

As a result, using the controller circuit 13 and the load device 14, itis possible to effectively utilize electric power generated from energyobtained from the user's living activities, according to usage of theload device 14.

According to the power system of the third embodiment, the controllercircuit 13 may supply electric power from the power storage circuit 12to the load device 14, simultaneously with power generating action ofthe power generating device 3, or after the predetermined time haselapsed from the power generating action of the power generating device3, or independently of the power generating action of the powergenerating device 3.

As a result, it is possible to operate the load device 14 at any moment,including during, after, and before operation of the power generatingdevice 3. Accordingly, it is possible to effectively utilize electricpower generated from energy obtained from the user's living activities,according to usage of the load device 14.

According to the power system of the third embodiment, the controllercircuit 13 may stop supplying electric power from the power storagecircuit 12 to the load device 14, when the voltage across the capacitorsC1 to C4 of the power storage circuit 12 is equal to or lower than thepredetermined lower limit voltage.

As a result, it is possible to fully utilize the energy of thecapacitors C1 to C4, and reliably operate the load device 14.

According to the power system of the third embodiment, the load device14 may include a lighting device.

As a result, the power system including the lighting device can beutilized for purposes of, e.g., lighting, warning to a suspiciousperson, and/or prevention of entry of a suspicious person.

According to the power system of the third embodiment, the load device14 may include a communication device.

As a result, the power system including the communication device can beutilized for purposes of, e.g., watching an elderly person and/ornotification of a suspicious person.

REFERENCE SIGNS LIST

1, 1-1, 1-2, 1A, 1B1, 1B2: HINGE COMPONENT (FIRST HINGE COMPONENT)

2, 2-1, 2-2, 2A, 2B: HINGE COMPONENT (SECOND HINGE COMPONENT)

3: POWER GENERATING DEVICE

10, 10-1, 10-2, 10A, 10B: HINGE DEVICE

11: RECTIFIER CIRCUIT

12: POWER STORAGE CIRCUIT

13: CONTROLLER CIRCUIT

14: LOAD DEVICE

14 a: LIGHT EMITTING DIODE (LIGHTING DEVICE)

14 b 1: WIRELESS TRANSMITTER (COMMUNICATION DEVICE)

14 b 2: WIRELESS RECEIVER

21, 21B: STATIONARY OBJECT

22, 22B: MOVABLE OBJECT

30 a, 30 b: HOUSING

31: INPUT SHAFT

32: DENT

33: GEAR

34, 34A to 34C: PROTRUSION

41: SCREW

C1 to C4: CAPACITOR

D1 to D4: DIODE

G1: GEAR MECHANISM

M1, M2: POWER GENERATOR

1. A hinge device comprising: first and second hinge components having acommon reference axis; and a power generating device, wherein the firstand second hinge components are engaged with each other, so as to berotatable about the reference axis relative to each other, and so thatone of the first and second hinge components supports the other, whereinthe power generating device comprises a housing and an input shaft, andgenerates electric power by rotation of the input shaft, wherein thehousing of the power generating device is fixed to the first hingecomponent, so that the input shaft of the power generating device ispositioned on the reference axis, and wherein the input shaft of thepower generating device is restrained to the second hinge component withrespect to a direction of rotation about the reference axis, so that theinput shaft of the power generating device rotates by as much asrotation of the second hinge component when the second hinge componentrotates about the reference axis.
 2. The hinge device as claimed inclaim 1, wherein the first hinge component has a through hole at aposition where the first and second hinge components are engaged witheach other, the through hole being formed so that the input shaft of thepower generating device protrudes from the first hinge component towardthe second hinge component, and wherein the second hinge component isformed to have a recess at a position where the first and second hingecomponents are engaged with each other, the recess accommodating theinput shaft of the power generating device protruding through thethrough hole.
 3. The hinge device as claimed in claim 2, wherein theinput shaft of the power generating device has a dent on a side surfaceof the input shaft, and wherein the input shaft of the power generatingdevice is restrained to the second hinge component with respect to adirection of rotation about the reference axis, by a screw extendingfrom outside of the second hinge component to the recess so as topenetrate the second hinge component and contact with the dent in therecess.
 4. The hinge device as claimed in claim 2, wherein the inputshaft of the power generating device and the recess of the second hingecomponent are shaped complementary to each other as seen from a point onthe reference axis.
 5. The hinge device as claimed in claim 1, whereinthe first and second hinge components are engaged with each other so asto be detachable from each other.
 6. The hinge device as claimed inclaim 1, wherein the first hinge component includes first and secondportions, wherein the second hinge component has first and second endsalong the reference axis, and the second hinge component is engaged atthe first end with the first portion of the first hinge component, andengaged at the second end with the second portion of the first hingecomponent, and wherein the first and second portions of the first hingecomponent are coupled to each other.
 7. The hinge device as claimed inclaim 1, wherein the power generating device comprises: a gear mechanismthat transmits rotation of the input shaft of the power generatingdevice at an increasing gear ratio; and a power generator that generateselectric power by rotation transmitted by the gear mechanism.
 8. A powersystem comprising: a hinge device, a rectifier circuit, a power storagecircuit, a controller circuit, and a load device, wherein the hingedevice comprises: first and second hinge components having a commonreference axis; and a power generating device, wherein the first andsecond hinge components are engaged with each other, so as to berotatable about the reference axis relative to each other, and so thatone of the first and second hinge components supports the other, whereinthe power generating device comprises a housing and an input shaft, andgenerates electric power by rotation of the input shaft, wherein thehousing of the power generating device is fixed to the first hingecomponent, so that the input shaft of the power generating device ispositioned on the reference axis, wherein the input shaft of the powergenerating device is restrained to the second hinge component withrespect to a direction of rotation about the reference axis, so that theinput shaft of the power generating device rotates by as much asrotation of the second hinge component when the second hinge componentrotates about the reference axis, wherein the rectifier circuitrectifies electric power generated by the power generating device of thehinge device; wherein the power storage circuit stores energy ofelectric power rectified by the rectifier circuit; wherein thecontroller circuit controls discharging of the power storage circuit;and wherein the load device that consumes electric power of the powerstorage circuit under control of the controller circuit.
 9. The powersystem as claimed in claim 8, wherein the power generating device, andat least one of the rectifier circuit, the power storage circuit, andthe controller circuit are disposed on the first hinge component of thehinge device.
 10. The power system as claimed in claim 8, wherein atleast one of the rectifier circuit, the power storage circuit, and thecontroller circuit is disposed on the second hinge component of thehinge device.
 11. The power system as claimed in claim 8, wherein one ofthe first and second hinge components of the hinge device is fixed to astationary object, and the other is fixed to a movable object, whereinweight of the movable object is supported by the first and second hingecomponents and the stationary object, and wherein, when the movableobject rotates with respect to the stationary object about the referenceaxis of the hinge device, the power generating device generates electricpower by rotation of the input shaft.
 12. The power system as claimed inclaim 11, wherein at least one of the rectifier circuit, the powerstorage circuit, and the controller circuit is disposed on thestationary object.
 13. The power system as claimed in claim 11, whereinat least one of the rectifier circuit, the power storage circuit, andthe controller circuit is disposed on the movable object.